Infiniti brakes

Just did rear brakes on Infiniti g25. Everyone said rear caliper pistons screw in, got the special tool to turn pistons. Turns out pistons do not turn. Just push in.and they went in easy. I probably could have pushed them in using my fingers. Easy job. Remove 1 caliper bolt, swing up caliper, retract piston, install pads. Probably 10 min each side. 2 yr old cars are nice. Not rusty as heck. Pads were almost at wear indicators. I did not see any sign of emer brake mechanism. No levers or extra brackets. How does e brake work on this car?

Most likely the e-brake is a drum brake on the inside of the rotor: